A density functional theory investigation on the geometries, electronic structures, and electron detachment energies of BS-, BS2-, B(BS)2- and B(BS)3- has been performed in this work. The linear ground-state structures of BS- (Ccov, 1∑+) and BS2- (D∞h, 1∑g+) prove to be similar to the previously reported BO- and BO2- with systematically lower electron detachment energies. Small boron sulfide clusters are found to favor the formation of-B=S groups which function basically as σ-radicals and dominate the ground-state structures of the systems. The perfect linear B(BS)2- (D∞h, 3∑g) and beautiful equilateral triangle B(BS)3- (D3h, 2A1") turn out to be analogous to the well-known C2v BH2 and D3h BH3, respectively. The electron affinities of BS, BS2, B(BS)2 and B(BS)3 are predicted to be 2.3, 3.69, 3.00 and 3.45 eV, respectively. The electron detachment energies calculated for BS-, BS2-, B(BS)2-, and B(BS)3- may facilitate future photoelectron spectroscopy measurements to characterize the geometrical and electronic structures of these anions.